I have a question about the recipe "Porcini and Rosemary Crusted Beef Tenderloin with Port Wine Sauce" from TasteFood. After deglazing the pan with Port, the recipes calls for wine, porcini liquid, and rosemary to be added and reduced. Does anyone consider adding beef broth here as well?

All things being equal except length, roasting time won't change much if at all. Time-per-pound estimates assume the object in question will get larger proportionally as the weight goes up (as would a chicken or turkey). Outside of attempting to coordinate time of service, relying on them is a really good way of wrecking an expensive cut of meat. As Pierino always says, it's done when it's done. And as I like to say, the only way of knowing for sure is to stick a thermometer in it.